Starting an exe with preset affinity [solved]

[11thHour]

I had a utility a number of years ago for windows 7. I could set the thread affinity for it, so whenever the application would run, it would run under that affinity group. Anyone recall a program that can do this? I don't recall if it required running the program as a process or not.

 

[VirtualLarry]

Process Lasso?

 

[11thHour]

Process Lasso?

Thanks. So far I'm not able to set a different affinity for different versions of the same exe with process lasso. I'm pretty sure there is something more simplified than this as well.

 

[TheRyuu]

If you can control how they're started you can use PsExec[1] to control the affinity.

For example if you want it to use CPU's 1 and 3:

PsExec.exe -a 1,3 foo.exe

Just keep in mind if you have a cpu that uses SMT (Hypterthreading) that you'll get two logical threads per core so remember to split it up properly if that's a concern.

[1] https://technet.microsoft.com/en-us/sysinternals/psexec.aspx

 

[KB]

You can create a batch file to run the exe using the start command with the desired affinity.

https://technet.microsoft.com/en-us/library/cc770297.aspx

 

[11thHour]

If you can control how they're started you can use PsExec[1] to control the affinity.

For example if you want it to use CPU's 1 and 3:

PsExec.exe -a 1,3 foo.exe

Just keep in mind if you have a cpu that uses SMT (Hypterthreading) that you'll get two logical threads per core so remember to split it up properly if that's a concern.

[1] https://technet.microsoft.com/en-us/sysinternals/psexec.aspx

Perfect, thanks TheRyuu! (And yes I'll be accounting for hyperthreading and as KB mentioned below, using a batch file execution.) The only catch is it works best putting psexec.exe into the target app's directory, otherwise when running, the targeted app thinks psexec's location is it's working directory, which confuses it when trying to find it's associated working files.

 

[TheRyuu]

You can create a batch file to run the exe using the start command with the desired affinity.

https://technet.microsoft.com/en-us/library/cc770297.aspx

I forgot that "start" could do that, don't even need psexec then, just make a batch file with the appropriate affinity mask (and as the documentation states it's a hex mask so it's different from psexec).